Multivariate Cox regression analysis exploring factors associated with lung cancer diagnosis in idiopathic pulmonary fibrosis patients
| Parameter | HR (95% CI) | p-value |
| Smoking exposure pack-years | ||
| <35 | Ref. | |
| ≥35 | 2.354 (1.278–4.339) | 0.006 |
| Emphysema | ||
| None | Ref. | |
| Present | 2.066 (1.220–3.498) | 0.007 |
HR: hazard ratio.